https://github.com/choptastic/hitori-erl

A hitori puzzle solver in Erlang
https://github.com/choptastic/hitori-erl

Last synced: 21 days ago
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A hitori puzzle solver in Erlang

• Host: GitHub
• URL: https://github.com/choptastic/hitori-erl
• Owner: choptastic
• License: mit
• Created: 2012-10-11T08:28:23.000Z (about 12 years ago)
• Default Branch: master
• Last Pushed: 2012-10-14T04:44:19.000Z (about 12 years ago)
• Last Synced: 2024-10-08T15:24:40.498Z (about 1 month ago)
• Language: Erlang
• Size: 101 KB
• Stars: 1
• Watchers: 2
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.markdown
  • License: MIT-LICENSE

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README

        
# Hitori-erl

A Hitori puzzle solver written in Erlang

(c) 2012 Jesse Gumm

Release under the MIT License

## Why

Just for fun

## Complexity and runspeed

This is not the fastest algorithm in the world, but it's at least slightly smarter than brute force.

It's basic run-time is O(N!) where N represents the number of "offending squares" (squares which are

potentially necessary to make black to solve). Speeding up the algorithm depends largely on determining

a better mechanism to find a proper "mark black", such as marking squares that *must* be black. The current

method of finding which squares to try first is basically any squares that are potentially black and are

found in both a row and a column. Beyond that, no intelligence is used to speed up the process.

## Usage

Load the source:

```erl

> c(hitori).

```

You can load your own puzzles by entering them as a 2-dimensional list. For example, to load a 5x5 puzzle:

```erlang

> B = hitori:from_list([

	[1,2,3,4,5],

	[2,3,4,5,1],

	[3,4,5,1,2],

	[4,5,1,2,3],

	[5,4,3,2,1]

]).

```

Then solve the puzzle with `hitori:solve/1`:

```erlang

> hitori:solve(B),

[{orig,[[1,2,3,4,5],

        [2,3,4,5,1],

        [3,4,5,1,2],

        [4,5,1,2,3],

        [5,4,3,2,1]]},

 {solved,[[1,2,x,4,5],

          [2,3,4,5,1],

          [3,4,5,1,2],

          [4,5,1,x,3],

          [5,x,3,2,x]]}]

```

It Returns the original unsolved puzzle and the solved puzzle with blacked out squares replaced with the atom `x`